With the use of unmanned aircraft (e.g., drones) becoming more widespread, the risks of mid-air collisions between unmanned aircraft, or between an unmanned aircraft and a manned aircraft, must be mitigated. Existing flight termination systems for unmanned aircraft may operate to terminate flight of an unmanned vehicle to avoid mid-air collisions, but require activation by a human operator from the ground, and thus are prone to error. For example, existing flight termination systems may detect a potential conflict (e.g., a future collision if both aircraft remained on their current course) and provide recommended avoidance maneuvers to the remote operator, but if the operator fails to take adequate action, then the mid-air collision may still occur. In current systems including situational awareness displays, the operator must recognize impending conflict (which is again prone to error) and mitigate it via a ground control link. If a functional data link between the operator and the aircraft is absent, then the operator would be unable to successfully prevent the collision. Additionally, such systems and associated sensors may be expensive, and/or too large or heavy to be included on smaller aircraft.